They introduced 3 heroes in the X-Men books that were active in WW2 who latter went on to join Mystique's Freedom Force team. They are Stonewall, Crimson Commando, and Super Sabre. Stonewall and Super Sabre are both dead last I knew, but Commando is still around though he is a cyborg now after suffering some major injuries on the same mission that Super Sabre was killed.